WASHINGTON (AP) -- Congress' midsummer to-do list may take until Christmas to clear.

At the top are maintaining the flow of highway funding, easing automatic budget cuts to the Pentagon and domestic agencies, renewing tax breaks and raising the debt limit. A misstep at any of several points could trigger a partial government shutdown.

Such a stack of unfinished business would be a time-consuming challenge in a well-oiled capital. But Washington has a case of chronic dysfunction, meaning there's little sense of urgency and the real potential for policymakers to end up doing the bare minimum - keeping the government on autopilot and avoiding an economy-rattling debt default.

"We ought to be meeting right now," said Rep. Steny Hoyer of Maryland, the second-ranking Democrat. "We're not doing that. There have been no discussions."

An eventual repeat of a government shutdown is a real possibility, though a short-term government-wide funding measure is likely in September and would buy time for negotiations. One of the biggest challenges involves finding spending cuts acceptable to Democrats and Republicans to pay for increases demanded by President Barack Obama for domestic priorities such as education and public works projects. Otherwise, agency budgets will largely be frozen by the return of automatic spending curbs.

If talks do not pan out, the sides may have no choice but to basically keep the government on autopilot, with spending frozen at current levels for another year, denying all but the most important increases.

The administration says Obama would veto such legislation, setting up a potential partial closing of the government similar to the 16-day shutdown in 2013 that was fueled by conservative activists and Sen. Ted Cruz, R-Texas, over Obama's health care law.

The president "will not accept a bill that locks in" the automatic spending limits, White House budget director Shaun Donovan said recently.

More pragmatic lawmakers want a sequel to a deal negotiated by Rep. Paul Ryan, R-Wis., and Sen. Patty Murray, D-Wash., that traded longer-term budget savings and user fees for two years of relief from the automatic agency cuts.

The most recent public posture from the White House is that Democrats and Republicans should take the lead in sorting it out. Republicans, however, are in no hurry for negotiations and say it's up to the White House to offer concrete spending cuts known as offsets to finance relief for agency budgets.

What Obama wants most is a break for domestic agencies that, on average, face a freeze in their day-to-day operating budgets. What Republicans want most is comparable help for the Pentagon. But agreeing on how to cut elsewhere in the long-term budget to pay for new spending now is a huge challenge, especially because a 2013 agreement vacuumed up many of the easier budget savings and new fees.

"It's harder than it was. Ryan-Murray used up most of the low-hanging fruit," said Ed Lorenzen, a budget expert and former House Democratic aide. "There's a little bit left, but it gets difficult to come up with big numbers."

Both Lorenzen and GOP aides noted that freezing spending at current levels would give Republicans some of the relief they are looking for the Pentagon anyway, because it would provide about $14 billion in higher war spending than the administration requested for the coming year.

Other issues being kicked to the end of the year include:

-increasing the government's $18.1 trillion debt limit, which budget experts say needs to be done in November or December. Obama says he will not allow Republicans to hold the measure hostage in an effort to win concessions from him. But if he succeeds, as he has in the past, Republicans probably would be more reluctant to give him victories elsewhere on his agenda.

-keeping highway and transit money flowing. Just Wednesday, the House passed an $8 billion measure funding federal highway programs through mid-December. Efforts in the Senate for a longer-term extension are iffy at best.

-renewing tax cuts for businesses and individuals, including the research and development tax credit and the deduction for sales taxes in states without an income tax.